Since being launched this morning, January 7, the solo track is overwhelming and has already topped five major music charts in Korea.

"Deja-Boo" took top spot on Genie Music, MelOn Music, Olleh Music, Bugs Music, and Naver Music overthrowing A Pink’s "LUV" from the pole position.

The rest of the Jonghyun’s debut album, which contains title track "Crazy (Guilty Pleasure)," is due to arrive on January 12, and will feature more collaborations with the likes of Younha, Wheesung, and IRON.